1. Field of the Invention
This invention relates to spacers or wheel chairs that are mounted on concrete reinforcement rods or rebar to keep the rebar from lying against the inner side of a concrete pouring form or mold where the rebar would be at the surface of the hardened concrete where it would be unsightly, exposed to weather, and be of reduced effectiveness in reinforcing the body of the concrete. Rebar comes in several diameters.
2. Description of the Prior Art
The art is replete with patented designs for rebar spacers. They include wheel-halves that clamp around the rebar, and wheels that hinge open and ratchet closed on the rebar.
U.S. Pat. No. Des. 223,701 patented May 30, 1972 by J. Lausch describes a spacer wheel support for rebar. The wheel has a polysided circumference. A cylindrical opening through the center of the wheel is attached by a radial rod to each vertex of the joining of the circumferential sides. A radial opening through a side of the cylinder to and through the circumference of the wheel is provided between two of the radial rods that are joined continuously by the circumference of the cylinder.
U.S. Pat. No. Des. 272,125 patented Jan. 10, 1984 by V. Doren describes a nailing block spacer that has a solid base having lateral axial nailing grooves and an axial tube atop the base that has flexible walls and a slot providing radial access to the tube by rebar. The base extends into the tube opposite the slot in a raised axial solid ridge.
U.S. Pat. No. 3,280,529 patented Oct. 25, 1966 by K. Reuss describes a spacer wheel having a circumferential wall and a cylindrical axial opening. A radial opening through a side of the cylinder to and through the circumference of the wheel is provided between two radial rods that are joined continuously by the circumference of the cylinder. About 90 degrees around from the radial opening, left and right rods extend radially from the cylinder wall to the circumference. Each rod has an angular dip at a point in its length to take up compression or tensile stress in the rod so that the open side of the cylinder can be forced apart to receive rebar. A short rod extends from the cylinder wall, radially outward opposite from the radial opening. The distal end of the short rod is spaced a sufficient distance from the circumferential wall such that the short rod prevents the cylinder from bending excessively at the base of the radial opening under the influence of large external downward or twisting load or stress transmitted to the spacer by the rebar.
It is one object of the invention to provide a spacer that can be attached to a rebar with gloved hands.
It is another object of the invention that the spacer be generally uniform in extension of its outermost surface from the rebar so that each spacer of a plurality of spacers mounted along the length of a bar will provide the same spacing from the form wall at each mounting location as the other spacers.
It is another object that a single spacer can be mounted on either of at least two different diameter bars.
It is another object that the spacer is molded in one piece.
An outer ring for contacting an object has an opening through it. A first resilient arm that is attached to the outer ring adjacent to the opening on a first side of the opening extends inward from the outer ring and terminates in a free end. A second arm that is attached to the outer ring adjacent to the opening on a second side of the opening extends inward from the outer ring, terminates in a second free end, and forms a slot with the first arm for moving rebar through the opening to the first and second free ends. The first and second arms form a first stop and a second stop spaced from the first stop for holding rebar that is moved into the opening and slot, between the first and second arms and the first and second stop. An inner ring that comprises the slot is attached to the first arm, the second arm, is spaced from the outer ring and from the first and second stops.
A spacer for rebar includes a body having an outer surface, a pair of arms attached to the body having free ends forming a seat for holding a first diameter rebar, a slot through the outer surface in communication with the pair of arms forming a pathway for moving a first diameter rebar radially inward of the outer surface into the seat, a bar attached to the body so that a portion of the bar extends toward the seat, the portion being yieldable radially outward from the seat to pressure of a second larger diameter rebar when the second rebar is in the seat. Preferably the portion is mounted on the body so that the portion is not significantly moved by the first diameter rebar when the first diameter rebar is in the seat. Preferably the spacer is a molded in one piece item.
Other objects and advantages of the invention will become apparent to persons skilled in the art from the ensuing description.